They must have worked hard getting this tune into their heads. It is a tricky, complicated piece, including a key change (going from F into Db for the Trio, unlike the original piano sheet music). It has several sections and many moments where the clarinet or the cornet have one-bar breaks or where a beat or two are completely silent. It is also very rhythmic and the overall effect can be, I think, terrifically exciting.
There are now several videos on YouTube of Tuba Skinny playing this tune. May I recommend that you seek them out?